Your South Philly yard as an ecosystem

Every 3rd Monday of the month, the group Transition Philadelphia (the local arm of "a movement of people making their communities more resilient in the face of peak oil, climate change and plain old economic hard times") hosts educational events that seek to inform about how to prepare our homes and neighborhoods for the end of cheap fossil fuels.
Tonight's event is about permaculture or, as their website puts it:

...learning to modify natural, self-contained ecosystems to produce a yield for us to eat while at the same time continually enhancing soil fertility and biodiversity, and managing food forests of perennial plants, familiar and new

Go to Transition Philadelphia's website for more info on the program (a short film with a guest speaker) and how to RSVP. Event begins at 6:30pm with a potluck dinner and main program starts at 7.
I've actually just started learning about permaculture over the past few weeks and am therefore a bit disappointed that I can't make it tonight at the South Philly Older Adults Center (northwest corner of E. Passyunk Ave. and Dickinson Street). In fact, not to tread on Sarah's beat, Alison and I finished planting our garden this weekend taking special care to include plenty of flowering annuals and some perennials (a new butterfly bush, for example) that will, in theory, attract pollinators and predators to fertilize our tomatoes, cucumbers and zucchini while protecting them from the white flies, black flies and worms that we had last year. And, unlike last year when our garden was almost all green, we have some great purples, reds and yellows going on (pictures to follow if everything we planted actually takes hold and thrives). Though not exactly permaculture since we didn't plant in such a way to keep us from having to add nutrients to our soil from compost, it is an ecosystem in the making. (Now, if only those good bugs can find their way to us!)
So if you're interested in figuring out how to take that bare patch of concrete behind your house and turn it into a self-supporting ecosystem, tonight's event is for you.